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-rw-r--r--source4/ntp_signd/config.mk3
-rw-r--r--source4/ntp_signd/ntp_signd.c415
2 files changed, 286 insertions, 132 deletions
diff --git a/source4/ntp_signd/config.mk b/source4/ntp_signd/config.mk
index 07c404d822..dd263fc88f 100644
--- a/source4/ntp_signd/config.mk
+++ b/source4/ntp_signd/config.mk
@@ -6,7 +6,8 @@
INIT_FUNCTION = server_service_ntp_signd_init
SUBSYSTEM = service
PRIVATE_DEPENDENCIES = \
- SAMDB NDR_NTP_SIGND
+ SAMDB NDR_NTP_SIGND \
+ LIBTSOCKET LIBSAMBA_TSOCKET
# End SUBSYSTEM NTP_SIGND
#######################
diff --git a/source4/ntp_signd/ntp_signd.c b/source4/ntp_signd/ntp_signd.c
index c611a75692..025ff2be84 100644
--- a/source4/ntp_signd/ntp_signd.c
+++ b/source4/ntp_signd/ntp_signd.c
@@ -27,6 +27,8 @@
#include "smbd/service_stream.h"
#include "smbd/process_model.h"
#include "lib/stream/packet.h"
+#include "lib/tsocket/tsocket.h"
+#include "libcli/util/tstream.h"
#include "librpc/gen_ndr/ndr_ntp_signd.h"
#include "param/param.h"
#include "dsdb/samdb/samdb.h"
@@ -35,6 +37,7 @@
#include "lib/ldb/include/ldb.h"
#include "lib/ldb/include/ldb_errors.h"
#include "../lib/crypto/md5.h"
+#include "system/network.h"
#include "system/passwd.h"
/*
@@ -55,67 +58,49 @@ struct ntp_signd_connection {
/* the ntp_signd_server the connection belongs to */
struct ntp_signd_server *ntp_signd;
- struct packet_context *packet;
+ struct tstream_context *tstream;
+
+ struct tevent_queue *send_queue;
};
-static void ntp_signd_terminate_connection(struct ntp_signd_connection *ntp_signdconn, const char *reason)
+static void ntp_signd_terminate_connection(struct ntp_signd_connection *ntp_signd_conn, const char *reason)
{
- stream_terminate_connection(ntp_signdconn->conn, reason);
+ stream_terminate_connection(ntp_signd_conn->conn, reason);
}
static NTSTATUS signing_failure(struct ntp_signd_connection *ntp_signdconn,
- uint32_t packet_id)
+ TALLOC_CTX *mem_ctx,
+ DATA_BLOB *output,
+ uint32_t packet_id)
{
- NTSTATUS status;
struct signed_reply signed_reply;
- TALLOC_CTX *tmp_ctx = talloc_new(ntp_signdconn);
- DATA_BLOB reply, blob;
enum ndr_err_code ndr_err;
- NT_STATUS_HAVE_NO_MEMORY(tmp_ctx);
-
signed_reply.op = SIGNING_FAILURE;
signed_reply.packet_id = packet_id;
signed_reply.signed_packet = data_blob(NULL, 0);
- ndr_err = ndr_push_struct_blob(&reply, tmp_ctx,
+ ndr_err = ndr_push_struct_blob(output, mem_ctx,
lp_iconv_convenience(ntp_signdconn->ntp_signd->task->lp_ctx),
&signed_reply,
(ndr_push_flags_fn_t)ndr_push_signed_reply);
if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
DEBUG(1,("failed to push ntp error reply\n"));
- talloc_free(tmp_ctx);
return ndr_map_error2ntstatus(ndr_err);
}
- blob = data_blob_talloc(ntp_signdconn, NULL, reply.length + 4);
- if (!blob.data) {
- talloc_free(tmp_ctx);
- return NT_STATUS_NO_MEMORY;
- }
-
- RSIVAL(blob.data, 0, reply.length);
- memcpy(blob.data + 4, reply.data, reply.length);
-
- status = packet_send(ntp_signdconn->packet, blob);
-
- /* the call isn't needed any more */
- talloc_free(tmp_ctx);
-
- return status;
+ return NT_STATUS_OK;
}
/*
receive a full packet on a NTP_SIGND connection
*/
-static NTSTATUS ntp_signd_recv(void *private_data, DATA_BLOB wrapped_input)
+static NTSTATUS ntp_signd_process(struct ntp_signd_connection *ntp_signd_conn,
+ TALLOC_CTX *mem_ctx,
+ DATA_BLOB *input,
+ DATA_BLOB *output)
{
- struct ntp_signd_connection *ntp_signdconn = talloc_get_type(private_data,
- struct ntp_signd_connection);
- NTSTATUS status = NT_STATUS_UNSUCCESSFUL;
- TALLOC_CTX *tmp_ctx = talloc_new(ntp_signdconn);
- DATA_BLOB input, output, wrapped_output;
const struct dom_sid *domain_sid;
struct dom_sid *sid;
struct sign_request sign_request;
@@ -128,100 +113,124 @@ static NTSTATUS ntp_signd_recv(void *private_data, DATA_BLOB wrapped_input)
uint32_t user_account_control;
int ret;
- NT_STATUS_HAVE_NO_MEMORY(tmp_ctx);
-
- talloc_steal(tmp_ctx, wrapped_input.data);
-
- input = data_blob_const(wrapped_input.data + 4, wrapped_input.length - 4);
-
- ndr_err = ndr_pull_struct_blob_all(&input, tmp_ctx,
- lp_iconv_convenience(ntp_signdconn->ntp_signd->task->lp_ctx),
+ ndr_err = ndr_pull_struct_blob_all(input, mem_ctx,
+ lp_iconv_convenience(ntp_signd_conn->ntp_signd->task->lp_ctx),
&sign_request,
(ndr_pull_flags_fn_t)ndr_pull_sign_request);
if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
DEBUG(1,("failed to parse ntp signing request\n"));
- dump_data(1, input.data, input.length);
+ dump_data(1, input->data, input->length);
return ndr_map_error2ntstatus(ndr_err);
}
/* We need to implement 'check signature' and 'request server
* to sign' operations at some point */
if (sign_request.op != SIGN_TO_CLIENT) {
- talloc_free(tmp_ctx);
- return signing_failure(ntp_signdconn, sign_request.packet_id);
+ return signing_failure(ntp_signd_conn,
+ mem_ctx,
+ output,
+ sign_request.packet_id);
}
/* We need to implement 'check signature' and 'request server
* to sign' operations at some point */
if (sign_request.version != NTP_SIGND_PROTOCOL_VERSION_0) {
- talloc_free(tmp_ctx);
- return signing_failure(ntp_signdconn, sign_request.packet_id);
+ return signing_failure(ntp_signd_conn,
+ mem_ctx,
+ output,
+ sign_request.packet_id);
}
- domain_sid = samdb_domain_sid(ntp_signdconn->ntp_signd->samdb);
- if (!domain_sid) {
- talloc_free(tmp_ctx);
- return signing_failure(ntp_signdconn, sign_request.packet_id);
+ domain_sid = samdb_domain_sid(ntp_signd_conn->ntp_signd->samdb);
+ if (domain_sid == NULL) {
+ return signing_failure(ntp_signd_conn,
+ mem_ctx,
+ output,
+ sign_request.packet_id);
}
/* The top bit is a 'key selector' */
- sid = dom_sid_add_rid(tmp_ctx, domain_sid, sign_request.key_id & 0x7FFFFFFF);
- if (!sid) {
- talloc_free(tmp_ctx);
- return signing_failure(ntp_signdconn, sign_request.packet_id);
+ sid = dom_sid_add_rid(mem_ctx, domain_sid,
+ sign_request.key_id & 0x7FFFFFFF);
+ if (sid == NULL) {
+ talloc_free(mem_ctx);
+ return signing_failure(ntp_signd_conn,
+ mem_ctx,
+ output,
+ sign_request.packet_id);
}
- ret = ldb_search(ntp_signdconn->ntp_signd->samdb, tmp_ctx,
- &res, samdb_base_dn(ntp_signdconn->ntp_signd->samdb),
- LDB_SCOPE_SUBTREE, attrs, "(&(objectSid=%s)(objectClass=user))",
- dom_sid_string(tmp_ctx, sid));
+ ret = ldb_search(ntp_signd_conn->ntp_signd->samdb, mem_ctx,
+ &res,
+ samdb_base_dn(ntp_signd_conn->ntp_signd->samdb),
+ LDB_SCOPE_SUBTREE,
+ attrs,
+ "(&(objectSid=%s)(objectClass=user))",
+ dom_sid_string(mem_ctx, sid));
if (ret != LDB_SUCCESS) {
- DEBUG(2, ("Failed to search for SID %s in SAM for NTP signing: %s\n", dom_sid_string(tmp_ctx, sid),
- ldb_errstring(ntp_signdconn->ntp_signd->samdb)));
- talloc_free(tmp_ctx);
- return signing_failure(ntp_signdconn, sign_request.packet_id);
+ DEBUG(2, ("Failed to search for SID %s in SAM for NTP signing: "
+ "%s\n",
+ dom_sid_string(mem_ctx, sid),
+ ldb_errstring(ntp_signd_conn->ntp_signd->samdb)));
+ return signing_failure(ntp_signd_conn,
+ mem_ctx,
+ output,
+ sign_request.packet_id);
}
if (res->count == 0) {
- DEBUG(5, ("Failed to find SID %s in SAM for NTP signing\n", dom_sid_string(tmp_ctx, sid)));
+ DEBUG(5, ("Failed to find SID %s in SAM for NTP signing\n",
+ dom_sid_string(mem_ctx, sid)));
} else if (res->count != 1) {
- DEBUG(1, ("Found SID %s %u times in SAM for NTP signing\n", dom_sid_string(tmp_ctx, sid), res->count));
- talloc_free(tmp_ctx);
- return signing_failure(ntp_signdconn, sign_request.packet_id);
+ DEBUG(1, ("Found SID %s %u times in SAM for NTP signing\n",
+ dom_sid_string(mem_ctx, sid), res->count));
+ return signing_failure(ntp_signd_conn,
+ mem_ctx,
+ output,
+ sign_request.packet_id);
}
- user_account_control = ldb_msg_find_attr_as_uint(res->msgs[0], "userAccountControl", 0);
+ user_account_control = ldb_msg_find_attr_as_uint(res->msgs[0],
+ "userAccountControl",
+ 0);
if (user_account_control & UF_ACCOUNTDISABLE) {
- DEBUG(1, ("Account %s for SID [%s] is disabled\n", ldb_dn_get_linearized(res->msgs[0]->dn), dom_sid_string(tmp_ctx, sid)));
- talloc_free(tmp_ctx);
+ DEBUG(1, ("Account %s for SID [%s] is disabled\n",
+ ldb_dn_get_linearized(res->msgs[0]->dn),
+ dom_sid_string(mem_ctx, sid)));
return NT_STATUS_ACCESS_DENIED;
}
if (!(user_account_control & (UF_INTERDOMAIN_TRUST_ACCOUNT|UF_SERVER_TRUST_ACCOUNT|UF_WORKSTATION_TRUST_ACCOUNT))) {
- DEBUG(1, ("Account %s for SID [%s] is not a trust account\n", ldb_dn_get_linearized(res->msgs[0]->dn), dom_sid_string(tmp_ctx, sid)));
- talloc_free(tmp_ctx);
+ DEBUG(1, ("Account %s for SID [%s] is not a trust account\n",
+ ldb_dn_get_linearized(res->msgs[0]->dn),
+ dom_sid_string(mem_ctx, sid)));
return NT_STATUS_ACCESS_DENIED;
}
- nt_hash = samdb_result_hash(tmp_ctx, res->msgs[0], "unicodePwd");
+ nt_hash = samdb_result_hash(mem_ctx, res->msgs[0], "unicodePwd");
if (!nt_hash) {
- DEBUG(1, ("No unicodePwd found on record of SID %s for NTP signing\n", dom_sid_string(tmp_ctx, sid)));
- talloc_free(tmp_ctx);
- return signing_failure(ntp_signdconn, sign_request.packet_id);
+ DEBUG(1, ("No unicodePwd found on record of SID %s "
+ "for NTP signing\n", dom_sid_string(mem_ctx, sid)));
+ return signing_failure(ntp_signd_conn,
+ mem_ctx,
+ output,
+ sign_request.packet_id);
}
/* Generate the reply packet */
signed_reply.packet_id = sign_request.packet_id;
signed_reply.op = SIGNING_SUCCESS;
- signed_reply.signed_packet = data_blob_talloc(tmp_ctx,
+ signed_reply.signed_packet = data_blob_talloc(mem_ctx,
NULL,
sign_request.packet_to_sign.length + 20);
if (!signed_reply.signed_packet.data) {
- talloc_free(tmp_ctx);
- return signing_failure(ntp_signdconn, sign_request.packet_id);
+ return signing_failure(ntp_signd_conn,
+ mem_ctx,
+ output,
+ sign_request.packet_id);
}
memcpy(signed_reply.signed_packet.data, sign_request.packet_to_sign.data, sign_request.packet_to_sign.length);
@@ -235,61 +244,177 @@ static NTSTATUS ntp_signd_recv(void *private_data, DATA_BLOB wrapped_input)
/* Place it into the packet for the wire */
- ndr_err = ndr_push_struct_blob(&output, tmp_ctx,
- lp_iconv_convenience(ntp_signdconn->ntp_signd->task->lp_ctx),
+ ndr_err = ndr_push_struct_blob(output, mem_ctx,
+ lp_iconv_convenience(ntp_signd_conn->ntp_signd->task->lp_ctx),
&signed_reply,
(ndr_push_flags_fn_t)ndr_push_signed_reply);
if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
DEBUG(1,("failed to push ntp error reply\n"));
- talloc_free(tmp_ctx);
return ndr_map_error2ntstatus(ndr_err);
}
- wrapped_output = data_blob_talloc(ntp_signdconn, NULL, output.length + 4);
- if (!wrapped_output.data) {
- talloc_free(tmp_ctx);
- return NT_STATUS_NO_MEMORY;
- }
-
- /* The 'wire' transport for this is wrapped with a 4 byte network byte order length */
- RSIVAL(wrapped_output.data, 0, output.length);
- memcpy(wrapped_output.data + 4, output.data, output.length);
-
- status = packet_send(ntp_signdconn->packet, wrapped_output);
-
- /* the call isn't needed any more */
- talloc_free(tmp_ctx);
- return status;
+ return NT_STATUS_OK;
}
/*
- receive some data on a NTP_SIGND connection
+ called on a tcp recv
*/
-static void ntp_signd_recv_handler(struct stream_connection *conn, uint16_t flags)
+static void ntp_signd_recv(struct stream_connection *conn, uint16_t flags)
{
- struct ntp_signd_connection *ntp_signdconn = talloc_get_type(conn->private_data,
- struct ntp_signd_connection);
- packet_recv(ntp_signdconn->packet);
+ struct ntp_signd_connection *ntp_signd_conn = talloc_get_type(conn->private_data,
+ struct ntp_signd_connection);
+ ntp_signd_terminate_connection(ntp_signd_conn,
+ "ntp_signd_recv: called");
}
/*
- called on a tcp recv error
+ called when we can write to a connection
*/
-static void ntp_signd_recv_error(void *private_data, NTSTATUS status)
+static void ntp_signd_send(struct stream_connection *conn, uint16_t flags)
{
- struct ntp_signd_connection *ntp_signdconn = talloc_get_type(private_data, struct ntp_signd_connection);
- ntp_signd_terminate_connection(ntp_signdconn, nt_errstr(status));
+ struct ntp_signd_connection *ntp_signd_conn = talloc_get_type(conn->private_data,
+ struct ntp_signd_connection);
+ /* this should never be triggered! */
+ ntp_signd_terminate_connection(ntp_signd_conn,
+ "ntp_signd_send: called");
}
-/*
- called when we can write to a connection
-*/
-static void ntp_signd_send(struct stream_connection *conn, uint16_t flags)
+struct ntp_signd_call {
+ struct ntp_signd_connection *ntp_signd_conn;
+ DATA_BLOB in;
+ DATA_BLOB out;
+ uint8_t out_hdr[4];
+ struct iovec out_iov[2];
+};
+
+static void ntp_signd_call_writev_done(struct tevent_req *subreq);
+
+static void ntp_signd_call_loop(struct tevent_req *subreq)
{
- struct ntp_signd_connection *ntp_signdconn = talloc_get_type(conn->private_data,
- struct ntp_signd_connection);
- packet_queue_run(ntp_signdconn->packet);
+ struct ntp_signd_connection *ntp_signd_conn = tevent_req_callback_data(subreq,
+ struct ntp_signd_connection);
+ struct ntp_signd_call *call;
+ NTSTATUS status;
+
+ call = talloc(ntp_signd_conn, struct ntp_signd_call);
+ if (call == NULL) {
+ ntp_signd_terminate_connection(ntp_signd_conn,
+ "ntp_signd_call_loop: "
+ "no memory for ntp_signd_call");
+ return;
+ }
+ call->ntp_signd_conn = ntp_signd_conn;
+
+ status = tstream_read_pdu_blob_recv(subreq,
+ call,
+ &call->in);
+ TALLOC_FREE(subreq);
+ if (!NT_STATUS_IS_OK(status)) {
+ const char *reason;
+
+ reason = talloc_asprintf(call, "ntp_signd_call_loop: "
+ "tstream_read_pdu_blob_recv() - %s",
+ nt_errstr(status));
+ if (reason == NULL) {
+ reason = nt_errstr(status);
+ }
+
+ ntp_signd_terminate_connection(ntp_signd_conn, reason);
+ return;
+ }
+
+ DEBUG(10,("Received NTP TCP packet of length %lu from %s\n",
+ (long) call->in.length,
+ tsocket_address_string(ntp_signd_conn->conn->remote_address, call)));
+
+ /* skip length header */
+ call->in.data +=4;
+ call->in.length -= 4;
+
+ status = ntp_signd_process(ntp_signd_conn,
+ call,
+ &call->in,
+ &call->out);
+ if (! NT_STATUS_IS_OK(status)) {
+ const char *reason;
+
+ reason = talloc_asprintf(call, "ntp_signd_process failed: %s",
+ nt_errstr(status));
+ if (reason == NULL) {
+ reason = nt_errstr(status);
+ }
+
+ ntp_signd_terminate_connection(ntp_signd_conn, reason);
+ return;
+ }
+
+ /* First add the length of the out buffer */
+ RSIVAL(call->out_hdr, 0, call->out.length);
+ call->out_iov[0].iov_base = call->out_hdr;
+ call->out_iov[0].iov_len = 4;
+
+ call->out_iov[1].iov_base = call->out.data;
+ call->out_iov[1].iov_len = call->out.length;
+
+ subreq = tstream_writev_queue_send(call,
+ ntp_signd_conn->conn->event.ctx,
+ ntp_signd_conn->tstream,
+ ntp_signd_conn->send_queue,
+ call->out_iov, 2);
+ if (subreq == NULL) {
+ ntp_signd_terminate_connection(ntp_signd_conn, "ntp_signd_call_loop: "
+ "no memory for tstream_writev_queue_send");
+ return;
+ }
+
+ tevent_req_set_callback(subreq, ntp_signd_call_writev_done, call);
+
+ /*
+ * The NTP tcp pdu's has the length as 4 byte (initial_read_size),
+ * packet_full_request_u32 provides the pdu length then.
+ */
+ subreq = tstream_read_pdu_blob_send(ntp_signd_conn,
+ ntp_signd_conn->conn->event.ctx,
+ ntp_signd_conn->tstream,
+ 4, /* initial_read_size */
+ packet_full_request_u32,
+ ntp_signd_conn);
+ if (subreq == NULL) {
+ ntp_signd_terminate_connection(ntp_signd_conn, "ntp_signd_call_loop: "
+ "no memory for tstream_read_pdu_blob_send");
+ return;
+ }
+ tevent_req_set_callback(subreq, ntp_signd_call_loop, ntp_signd_conn);
+}
+
+static void ntp_signd_call_writev_done(struct tevent_req *subreq)
+{
+ struct ntp_signd_call *call = tevent_req_callback_data(subreq,
+ struct ntp_signd_call);
+ int sys_errno;
+ int rc;
+
+ rc = tstream_writev_queue_recv(subreq, &sys_errno);
+ TALLOC_FREE(subreq);
+ if (rc == -1) {
+ const char *reason;
+
+ reason = talloc_asprintf(call, "ntp_signd_call_writev_done: "
+ "tstream_writev_queue_recv() - %d:%s",
+ sys_errno, strerror(sys_errno));
+ if (!reason) {
+ reason = "ntp_signd_call_writev_done: "
+ "tstream_writev_queue_recv() failed";
+ }
+
+ ntp_signd_terminate_connection(call->ntp_signd_conn, reason);
+ return;
+ }
+
+ /* We don't care about errors */
+
+ talloc_free(call);
}
/*
@@ -297,37 +422,65 @@ static void ntp_signd_send(struct stream_connection *conn, uint16_t flags)
*/
static void ntp_signd_accept(struct stream_connection *conn)
{
- struct ntp_signd_server *ntp_signd = talloc_get_type(conn->private_data, struct ntp_signd_server);
- struct ntp_signd_connection *ntp_signdconn;
+ struct ntp_signd_server *ntp_signd = talloc_get_type(conn->private_data,
+ struct ntp_signd_server);
+ struct ntp_signd_connection *ntp_signd_conn;
+ struct tevent_req *subreq;
+ int rc;
+
+ ntp_signd_conn = talloc_zero(conn, struct ntp_signd_connection);
+ if (ntp_signd_conn == NULL) {
+ stream_terminate_connection(conn,
+ "ntp_signd_accept: out of memory");
+ return;
+ }
+
+ ntp_signd_conn->send_queue = tevent_queue_create(conn,
+ "ntp_signd_accept");
+ if (ntp_signd_conn->send_queue == NULL) {
+ stream_terminate_connection(conn,
+ "ntp_signd_accept: out of memory");
+ return;
+ }
+
+ TALLOC_FREE(conn->event.fde);
- ntp_signdconn = talloc_zero(conn, struct ntp_signd_connection);
- if (!ntp_signdconn) {
- stream_terminate_connection(conn, "ntp_signd_accept: out of memory");
+ rc = tstream_bsd_existing_socket(ntp_signd_conn->tstream,
+ socket_get_fd(conn->socket),
+ &ntp_signd_conn->tstream);
+ if (rc < 0) {
+ stream_terminate_connection(conn,
+ "ntp_signd_accept: out of memory");
return;
}
- ntp_signdconn->conn = conn;
- ntp_signdconn->ntp_signd = ntp_signd;
- conn->private_data = ntp_signdconn;
- ntp_signdconn->packet = packet_init(ntp_signdconn);
- if (ntp_signdconn->packet == NULL) {
- ntp_signd_terminate_connection(ntp_signdconn, "ntp_signd_accept: out of memory");
+ ntp_signd_conn->conn = conn;
+ ntp_signd_conn->ntp_signd = ntp_signd;
+ conn->private_data = ntp_signd_conn;
+
+ /*
+ * The NTP tcp pdu's has the length as 4 byte (initial_read_size),
+ * packet_full_request_u32 provides the pdu length then.
+ */
+ subreq = tstream_read_pdu_blob_send(ntp_signd_conn,
+ ntp_signd_conn->conn->event.ctx,
+ ntp_signd_conn->tstream,
+ 4, /* initial_read_size */
+ packet_full_request_u32,
+ ntp_signd_conn);
+ if (subreq == NULL) {
+ ntp_signd_terminate_connection(ntp_signd_conn,
+ "ntp_signd_accept: "
+ "no memory for tstream_read_pdu_blob_send");
return;
}
- packet_set_private(ntp_signdconn->packet, ntp_signdconn);
- packet_set_socket(ntp_signdconn->packet, conn->socket);
- packet_set_callback(ntp_signdconn->packet, ntp_signd_recv);
- packet_set_full_request(ntp_signdconn->packet, packet_full_request_u32);
- packet_set_error_handler(ntp_signdconn->packet, ntp_signd_recv_error);
- packet_set_event_context(ntp_signdconn->packet, conn->event.ctx);
- packet_set_fde(ntp_signdconn->packet, conn->event.fde);
- packet_set_serialise(ntp_signdconn->packet);
+ tevent_req_set_callback(subreq, ntp_signd_call_loop, ntp_signd_conn);
}
static const struct stream_server_ops ntp_signd_stream_ops = {
.name = "ntp_signd",
.accept_connection = ntp_signd_accept,
- .recv_handler = ntp_signd_recv_handler,
+ .recv_handler = ntp_signd_recv,
.send_handler = ntp_signd_send
};